Abstract: The problems of water system in methanol to olefin plant are analyzed. The major problems in quench system are the fouling on tower plates and the high solid content. The components with high-melting-point solidify on cold tower plates is the main course of fouling, and pre-spray before tower plate can handle this. PAM was used to decrease solid content of quench water. The major problems in washing system are the increase of pressure drop, and the decrease of heat transfer effect. It is analyzed that the gradient solidification of multi methyl benzene in system and blend with catalysts are the main reasons. Hence the washing tower should separate into several segments, and decrease the temperature gradient in segments while increase that between segments. Cyclone before washing tower is able to decrease solid content in washing water.

Key words: methanol to olefin, quench system, washing system, solid content, fouling

摘要： 对甲醇制烯烃（MTO）工业化装置水系统面临的主要问题进行了深入分析。急冷系统主要面临急冷塔塔板结垢、急冷水固含量高的问题：塔板结垢系高温产品气遇低温塔板时产品气中的高熔点组分冷凝析出所致，通过设置塔板前喷水预降温可以有效缓解；使用聚丙烯酰胺絮凝剂对急冷水进行处理可以有效降低固含量。水洗系统主要面临水洗塔压降升高、水洗水换热器换热效果下降等问题，其主要原因在于多甲基苯物质在系统中发生梯度冷凝，并与催化剂和泥堵塞。因此将水洗塔分段设置，并降低段内温差，增大段间温差，可以有效缓解塔板结蜡现象；同时产品气入水洗塔前设置旋风分离器，以降低水洗水固含量。

关键词: 甲醇制烯烃, 急冷系统, 水洗系统, 固含量, 结垢